This invention relates generally to new and improved apparatus and processes for facilitating reaction between analyte contained in a sample and test reagent system, and more particularly relates to new and improved apparatus and processes for enhancing facilitation of reaction between analyte contained in a sample and test reagent system wherein flow produced by capillary attraction, particularly turbulent flow, is utilized to bring a liquid one of sample and test reagent system into contact, particularly turbulent contact, with the other of the sample and test regent system to enhance facilitation of the reaction.
It will be understood that the term "analyte" is used in the specification and the appended claims to define something which is being analyzed, or determined, i.e. determined as to its presence or absence or presence to a significant extent, on the basis of whether or not a reaction, or a significant reaction, occurs with a test reagent system. Further, it will be understood that the term "test reagent system" as used in the specification and appended claims is used to define a system which has been adapted to react with the analyte upon its presence or presence to a significant extent. Analyte is typically contained in a sample, usually a liquid sample, for example the sample may be blood and the blood may be analyzed or a determination made with regard thereto as to whether or not antibodies to the human immunodeficiency virus (HIV) are present in the blood such antibodies being the analyte. The test reagent system may be latex beads coated with a certain human immunodeficiency virus (HIV) antigen, upon the antibodies being present and brought into contact with the antigen, an agglutination reaction occurs indicating a positive analysis or determination; thus it will be understood further that in the context of the present invention the analyte may be an antibody reagent and the test reagent system may be an antigen reagent, or vice versa. By way of further example, the analyte may be glucose contained in blood or blood serum, the test reagent system may be the Trinder reagent system, a colorimetric test reagent system, and upon the analyte being brought into contact with the Trinder test reagent system, and glucose analyte being present in the blood or blood serum sample, a change in color occurs to indicate, or provide the determination that, glucose is present in the sample. Other examples of analyte contained in a sample, e.g. liquid sample, are penicillin contained in milk, amylase contained in saliva, sodium chloride contained in sweat, bacteria contained in carrot juice; in each of these instances, a suitable test reagent system, e.g. a liquid test reagent system, would be provided to react with the analyte upon the analyte being present at least to a significant extent.
Analyte determination or analysis has been advanced by innumerable technological advances, yet many of the analyte determinations performed today require handling of sample containing the analyte and/or test reagent system; the use of ancillary equipment such as timers, test reagent system and/or sample containers or cuvettes; mixing devices (e.g. centrifuges, rotary mixers, mixing coils, pump, etc.) and reading devices (e.g. scanners, photometers, etc.). Additionally, the amounts of sample containing analyte/test reagent system required for testing may be large thereby increasing the cost per test to the point where they are at least undesirably high if not prohibitive for a large group of the present population.
Slide tests, and slide test apparatus are well known to those skilled in the analyte determination or analysis art, yet to perform a slide test requires the addition and mixing of the sample containing analyte and test reagent system for a prescribed time period whereafter the reaction, or test result, is then interpreted by direct visual observation or by an automatic optical reader. Typical slide test apparatus and processes are disclosed in U.S. Pat. No. 4,022,521 to Hall et al. patented May 10, 1977, U.S. Pat. No. 4,088,448 to Lilja et al. patented May 9, 1978, U.S. Pat. No. 4,171,866 to Tolles patented Oct. 28, 1979, and U.S. Pat. No. 4,596,695 to Cottingham patented Jun. 24, 1986. While the slide test apparatus and process disclosed in such prior art United States Patents may work well for their intended purposes, it has been found that there exists a present need for new and improved reaction apparatus and processes wherein, for example, the reaction time between the analyte and test reagent system is shortened (this is particularly important in presently needed large scale testing such as for the presence of the antibody to HIV in blood), facilitation of reaction between the analyte and test reagent system enhanced such as by increasing the number of reaction sites available therebetween (this is particularly important in those instances where for reason of cost, efficiency and timesaving it is desirable to use minimal amounts of analyte and test reagent system while retaining analyte determination sensitivity----this is especially important if the cost of the test reagent system is high or the amounts available for use are limited), and optical determination of the reaction enhanced.
By way of further background of the present invention, it will be understood that the term "optical determination" as used in the specification and the appended claims means determination of the presence or absence of a reaction between analyte and test reagent system, for example by the human eye, a beam of light such as used in a turbidimeter, and the like. By way of still further background, and as taught in detail below, the apparatus and processes of the present invention utilize "capillary means" and that "capillary means" is used in the specification and the appended claims to include a capillary tube having a small bore, or other structure such as a relatively large body of material having a small bore, into which bore a liquid may be elevated or drawn by capillary attraction. Still further, it will be understood that the term "liquid" as used in the specification and the appended claims means a liquid or other medium capable of being elevated or drawn into capillary means by capillary attraction. Still further it will be understood that the term "turbulent flow" as used in the specification and the appended claims is used to define fluid, e.g. liquid flow, in which the velocity at a given point changes constantly in magnitude and direction----contrasted with laminar flow; the term "turbulent flow" is further defined hereinbelow in the Description of the Invention and further contrasted with laminar flow.